Bridging tool



Jan. 7, 1969 M. D. KILGORE BRIDGING TOOL Filed Nov. 24, 1965 INVENTOR MAR/0ND. X/(G'OPf M 9 j Jan. 7,1969 M. D. KILGORE 3,420,304

BRIDGING TOOL Filed Nov. 24, 1965 Sheet .2 of 2 INVENTOR MA R/O/V 0. K /L GORE United States Patent 6 Claims ABSTRACT OF THE DISCLOSURE A bridging tool arranged to be set in a cased well bore. The bridging tool includes an annular packer adapted to be set and held in sealing engagement with the casing and has a tubular member projecting upwardly from the packer. The tubular member is provided, near its upper interior end, with means for receiving a releasable plug. The plug is arranged to prevent the entrance of materials into the interior of the tubular member. The exterior of the tubular member is provided with means for receiving a setting tool whereby the annular packer can be set in the well casing. The tubular member is also provided with gudgeon pins adapted to engage the lower interior end of a production tubing so that the production tubing can be releasably attached to the bridging tool.

This invention is concerned with a bridging tool arranged to be lowered and set in a well casing, and is particularly concerned with a bridging tool which may be selectively closed to isolate the areas in the casing above and below the tool or opened to provide a flow passage therethrough, to permit production from a formation in the well below the tool.

In completion or work over operations in oil wells it is often desirable that a lower formation in the well be plugged off and isolated from an upper Zone while the upper zone is being treated by various well operations.

T o accomplish such purpose bridge plugs and drillable or permanent packers having closed bores therein are set in the casing between the formations.

In some instances packers have been employed having a rupturable or disengageable plug in the bore thereof Which can be disengaged and pushed out of the bore, so that the packer would first provide a bridge plug and then upon the removal of the push-out plug a production packer .through which fluid can be produced.

In some instances such packers were provided with wire line retrievable plugs in the bores thereof intended to be removed after treating and workover operations are carried on above same, and wherein the bore was arranged to receive a latch-in stinger attached to the lower end of the production string.

However, in all such installations the bore or stinger receiving passage in the packer are upwardly facing female receptacles which are open and exposed during the treating or workover operations thereabove so that debris and settlings, such as cement stringers, scaling, sand, etc., could fall thereinto, thereby making it difficult if not impossible to push the expellable plug therefrom, or remove the wire line retrievable plug therefrom, and preventing the latch-in stinger from being connected therein.

Summary of the invention This invention provides an improved bridging tool that includes a packer arranged to be set against the wall of the Well casing and having a bore extending therethrough; a tubular member attached to the packer in communication with the bore and extending upwardly therefrom; means in the upper end of the tubular member arranged to receive a removable closure member to close the bore therethrough, whereby the tubular member may be selectively closed and opened at the upper end thereof.

The present invention is intended to overcome the foregoing shortcomings of tools of this general type, and among the objects thereof are the following:

To provide a bridging tool adapted to be run into an oil well on a wire line and set by a conventional wire line supported setting gun.

To provide a bridging plug having a removable plug or closure member therefor which may be alternately removed therefrom or placed therein, as conditions may require, so that the bridging plug may alternately serve as a bridging plug or production packer.

To provide a bridging plug and packer member with an insertable and removable plug for selectively closing or opening the passage therethrough, wherein debris and settlings in the well are prevented from accumulating in the passage wherein the removable plug is seated.

To provide in such a bridging tool means to engage a tubing string about the receptacle for the removable plug before the removable plug is removed.

To provide a tubular receptacle for the insertable and removable plug which extends upwardly from the packer, and wherein the removable plug is positioned in the upper end of the tubular member and extends outwardly thereof, so that the plug and said tubular member guides settlings and debris from the treating or remedial operations carried out in the well above the tool about the tubular member into an annulus between same and the casing, so that such settlings and debris cannot accumulate in the bore of the plug receptacle, and so that such debris may be easily removed by an overshot tool passed about the upwardly extending tubular member.

To provide a tubular production string having means on the lower end thereof arranged to pass about and sealingly engage an upwardly extending tubular plug receptacle, and which may have means on the lower end thereof arranged to remove settlings and debris about the upwardly extending tubular member.

To provide a combination packer and bridging plug having an upwardly extending plug receptacle thereon which is disengageably attached to the tension member of a wire line setting gun in such a manner that the tension member of the wire line setting gun is automatically detached therefrom to permit the withdrawal of the setting gun upon the application of a predetermined force thereagainst.

Other and further objects of the invention will become apparent upon reading the detailed specification herein after following and by referring to the drawings annexed FIGURE 3 is a crosssectional elevational view of the bridging tool after testing, treating, or remedial workover procedures have been carried out thereabove, and a tubing string, run from the surface, has been connected in sealing engagement for production from a formation in the well below the tool,

FIGURE 4 is a transverse sectional view taken on the line IV-IV of FIGURE 3, and

FIGURE is an elevational view of one of the 1- slots with a gudgeon pin therein.

Referring first to FIGURE 1, there is an outer tubular sleeve 1 and a tension rod 2 of a conventional wire line setting mechanism, or gun, commonly used in the oil industry. When actuated by an electrical impulse from the surface an explosive charge in the gun causes relative motion between the outer sleeve 1 and the rod 2, resulting in a downward force being exerted on the outer sleeve 1 and an upward force exerted through the rod 2, which is adapted to set the packer, as hereinafter described.

A setting sleeve 3 is attached to the outer sleeve 1 by mating threads 4 and is attached to a slip guide 5 by mating threads 6.

The upper slips 7 of a permanent-type packer P are disengageably supported to the slip guide 5 by interengaged shoulders 5a which are retained in interlocked engagernent by garter spring 8 in retracted position on upper expander cone 9 of the packer assembly.

In the running and unset condition of the tool, the upper cone 9 is positioned on the mandrel 10 and retained in the extended, unset position by shear screws 11 engaged with the mandrel.

The mandrel 10 is threadedly engaged to a guide body 12 by matching threads 13. Lower slips 14 abut the guide body 12 and are held in extended retracted position on the mandrel 10 by shear screws 15 which extend through said lower slips 14, the lower expander cone 1 6, and engage the mandrel 10 in blind holes 17.

Between the upper cone 9 and the lower cone 16, and extending about the mandrel 10, there is a resilient packing sleeve 18, adapted to be sealingly compressed therebetween in a longitudinal direction to fill the annular space between the mandrel 10 and the well casing 19. When the packer P is set, as hereinafter described, the sealing engagement of packing sleeve 18 is retained by the upper slips 7 in engagement with the casing which prohibit upward relaxation, and by the lower slips 14 in engagement with the casing, which prohibit downward relaxation of the sleeve 18.

Concentric alignment of the slip guide 5 and upper slips 7 is maintained (in the unset or running-in position) by a guide shoulder 20 about the tubular receptacle It A tubular plug receptacle 21 is attached to the mandrel 10 by companion threads 21a and extends above the packer asembly P.

An annular groove 22 is provided about the upper end of receptacle 21 for engagement with flexible collet fingers 23, which are adapted to transmit the setting force to the packer, said force being of a predetermined value determined by a shear ring 24 threadedly engaged to a retainer head 25, which is threadedly attached to the rod 2 at the companion threads 26. The retainer head 25 includes a dependent skirt 27 which has an annular inwardly turned flange 27a about the lower end thereof engaging the collet fingers 23, thereby prohibiting expansion thereof until the predetermined setting force has ruptured the shear ring 24 and allowed relative axial rnovement between the collet fingers and the dependent skirt 27.

The upwardly extending receptacle 21 has an inner annular recess 28 formed therein, at the upper end thereof, adapted to receive a conventional tubing plug 29. The tub ing plug 29 may be retrievably inserted in the bore of receptacle 21 and engaged with the recess 28, either manually before the tool is run, or by conventional wire line equipment, which is well known in the art, after the bridging tool has been run and subsequent engagement to a production string has been achieved. The tubing plug 29 effectively resists pressure from either direction and provides the bridging tool with an effective separation barrier. The plug 29 may be selectively inserted in or removed from the receptacle 21 to convert the packer P to a bridging plug or a production packer, as the circumstances may require.

The tubing plug 29 is a conventional type of plug which may be run and retrieved on a wire line from the surface, and includes a seal 29a to seal against the bore of receptacle 21, a fishing neck 2% and pivoted dogs 29c, arranged to be expanded outwardly into engagement with the recess 28. It is not thought necessary to illustrate same in detail. A suitable form of such a plug is the Otis PN plug illustrated in the Composite Catalog of Oil Field Equipment and Services, 1964-65, volume 3, page 3737.

When the tool is set in the casing and the running string is removed, as shown in FIGURE 2, there is provided an annular space or void 30 between the receptacle 21 and the casing 19 above the packer P.

With the bridging tool and plug 29 in position, as shown in FIGURE 2, any debris or settlings, such as scale, cement strings, etc., resulting from remedial or completion work carried on above the tool will settle in said annular space 30 and will be effectively prevented from accumulating in the bore of the packer or other interior space in the tool. When accumulated in the annular space 30 said debris can be effectively washed out and removed by a conventional overshot tool to prevent potential and troublesome involvement with the sealing engagement of the production string with the bridging and/or production tool which is described with relation to FIGURE 3.

Referring to FIGURE 3, there is a production string 31 communicating with the surface of the well and attached by mating threads 32 to a packing sleeve or seal housing 33. There is an interior shoulder 34 in the packing sleeve 33 against which is abutted a multiplicity of seal rings 35 and spacers 36, adapted for sealing engagement with the outer surface of the plug receptacle 21. Said seal rings and spacers are supported from below by a J-slot housing 37 which is attached to the packing sleeve 33 by the matching threads 38. The J-slot housing 37 has opposed J-slots 37a formed therein and adapted for releasable latching engagement with the gudgeon pins 39 formed on receptacle 21, as shown in FIGURES 3, 4, and 5. There is a guide 40 attached to the ]-slot housing 37 at matching threads 41. Downwardly extending blades 40a may be provided on guide 40 so that the sleeve 33 can be rotated or manipulated to displace settlings in space 30 while the production string is being run into sealing engagement with receptacle 21.

In operation, the bridging tool is assembled to the setting mechanism with the tubular receptacle 21 suspended thereto by engagement of the groove 22 with the collet fingers 23. The packer assembly P, comprising the mandrel 10, the guide body 12, upper slips 7, lower slips 14, upper cone 9, lower cone 16, and packing element 18, is supported and held in the extended or unset position by the upper shear screws 11 and lower shear screws 15. The upper slips 7 are additionally disengageably held and supported by interlocking engagement with the slip guide 5. In this condition the tool is lowered on an electrical conductor cable (not shown) to the required depth in the well, with the tubing plug 29 in place to close the bore through the packer P.

When the required depth has been obtained, the setting gun (not shown) is actuated by an electrical impulse from the surface and relative motion occurs between the outer sleeve 1 and the rod 2 of the setting gun. The sleeve 1 moves downward and rod 2 moves upward. The downward motion of the outer sleeve 1 is transmitted through the setting sleeve 3 and guide 5 to the upper slips 7 which move downwardly and outwardly on the upper expander cone 9 to bring the slips 7 into anchoring contact with the casing 19. Further relative motion between the outer sleeve 1 and the rod 2 will, sequentially, shear both the upper and lower shear screws 11 and 15 and cause the lower anchoring combination of slips 14 and expander cone 16 to move toward the upper anchoring mechanism to move slips 14 outwardly into anchoring engagement with the casing and in the process compressing the packing element 18 into sealing engagement with the casing 19.

When the proper degree of compression is obtained in the packing element, the predetermined shear value of the shear ring 24 will be attained to cause rupture thereof and disconnection of the collet from support 25 and allow relative axial motion between the collet fingers 23 (downwardly) and the depending portion 27 of the retainer 25 (upwardly). This motion will place the collet fingers in position to expand outwardly and release the mandrel extension or receptacle 21 from the setting gun assembly so that it may be withdrawn from the well, leaving the packer assembly in the condition shown in FIGURE 2. The sheared-off portion of ring 24 is retained within the collet; the collet is caught on the upper shoulder of flange 27a and withdrawn with the setting gun assembly.

During the foregoing operations the upper slips 7 in extending outwardly to reach anchoring position between the cone 9 and the casing 19, have been expanded outwardly to disengage interengaged shoulders 5a to thereby release them from the slip guide 5. The setting mechanism is then removed from the well.

In this stage (FIGURE 2) the bridging tool is functioning as a bridge plug, but with the important advantage of having the bridging member, i.e., the tubing plug 29, not only removable but removable and replaceable as many times as may -be required. This action of removing and/or replacing the bridging plug 29 is carried out by means of a conventional wire line equipment (not shown) lowered from the surface.

It is important to note that in its function as a bridge plug, the bridging tool provides not only a bridging action, but, by virtue of the location of the plug 29 in the extreme upper portion of the mandrel extension 21, so that the plug extends outwardly of the bore thereof, it will direct any settlings, cement stringers, scaling, etc., which may settle to this position in the well from operations above, to the annular space 30, from which said settlings, can be easily removed by a conventional washover shoe passed over the receptacle 21. The receptacle 21, with plug 29 therein, provides a closed concentric male member extending upwardly from the packer P and the position of the plug 29 in the extreme upper portion of the bore of the receptacle 21 prevents settlings from passing into the bore of the packer and directs them into the annular space 30 where they can be removed, and do not interfere with opening or closing the packer bore to attain the objects of this invention.

When the required remedial, workover or testing action above the bridging tool has been completed, a production string 31 (FIGURE 3) is run from the surface. This string may incorporate additional packers or tools as required in the well schedule, and has attached to its lower end the female portion of the sealing mechanism, comprised of sleeve 33 and seals 35, which may, be passed over the receptacle 21 to provide a fluid-tight joint between said members. Thus, sealed communication will be established with the bore of the bridging tool after removal of plug 29. The J-slots 37a are rotated into engagement with gudgeon pins 39 to rigidly attach the production string to the bridging tool. The J-slot housing may carry washover blades 40a which would be effective in displacing, loosening, and cleaning out the annular space 30 to permit the sealing sleeve 33 and seal assembly 35-36 to pass over receptacle 21 into sealing engagement therewith.

When the outer half of the sealing means has been positioned overthe upper end of the receptacle 21, the J-slot latching means will be rotated in position to rigidl hold 6 the sealing means in telescoped and sealing position as shown in FIGURE 3.

The tubing plug 29 can now be removed from the bore of receptacle 21 to establish communication between production string 31, and the bore of the bridging tool, by means of conventional surface operated wire line equipment. Furthermore, the tubing plug 29 can be replaced in the bore of receptacle 21, and the production string 31 removed, by unlatching the J -slot at any time workover operations need to be carried out above the packer P or for any other reason it is desired to close off the well below packer. P.

It will be seen that I have provided a combination bridge plug and production packer, which may be run and set on a wire line, which may be alternately converted from a bridge plug to a production packer by wire line operation, and wherein the deposit of settlings in the plug receiving bore, both while the device is serving as a bridge plug and as a production packer, is positively prevented.

Having described my invention I claim:

1. In a bridging tool, a packer arranged to be set against the wall of a well casing and having a bore therethrough; a relatively short tubular member attached to the packer in communication with the bore and extending upwardly therefrom and having an upper end; a removable closure member sized to fit into said tubular member and extending at least to said upper end; means in the interior of said tubular member near said upper end of the tubular member arranged to receive and releasably connect said removable closure member to said tubular member to close the bore and to prevent the entrance of material into the interior of said tubular member from above said bridging tool.

2. The combination called for in claim 1 with the addition of means on the exterior of and near the upper end of the tubular member for attachment of a running tool.

3. The combination called for in claim 1 with the addition of means intermediate the ends of the tubular memher on the exterior thereof for disengagea'ble attachment thereto of a housing passed thereover.

4. In a well tool, a packer arranged to be set against the wall of the well casing, said packer having a *bore therethrough; a tubular member attached to the packer in communication with said bore and extending upwardly therefrom; a setting gun tension rod disengageably attached to the upper end of the tubular member; a setting gun sleeve surrounding the rod and being disengageably attached to the upper end of the packer; and a removable closure member arranged to be disposed in the upper end of the bore of the tubular member.

5. The combination called for in claim 4 wherein the means for disengageable attachment of the tension rod to the tubular member comprises a collet engaged about the tubular member; and frangible means attached between the collet and the rod arranged to be broken upon a predetermined force being exerted thereagainst, to thereby release the rod from the tubular member.

6. In a bridging tool, a packer arranged to be set against the wall of the well casing and having a bore therethrough; a tubular member attached to the packer in communication with the bore and extending upwardly therefrom; means in the upper end 'of the tubular member arranged to receive the removable closure member to close the bore therethrough, whereby the tubular member may be selectively closed and opened at the upper end thereof; and, means on the upper end of the tubular member for attachment of a running tool, said means for attachment including a groove extending about the outer side of the tubular member, a plurality of collet fingers disengageably attached to the groove, shearable means holding the fingers in engagement with the tubular member, said collet fingers being arranged to move outwardly of engagement with the groove when the shearable means is broken.

(References on following page) 7 8 References Cited 3,062,292 11/1962 Lowrey et a1. 166123 UNITED STATES PATENTS 3,220,480 11/1965 MYfiI'S 16663 6/1919 Mack 166133 JAMES A. LEPPINK, Primary Examiner. 2/1942 Ragland et a1. 1661 14 5 5/1960 McCune 166114 U.S. Cl. X.R. 5/1961 Baker 166114 166133, 181 

